The UBIK® OPC Unified Architecture interface module enables interfacing between a UBIK® server and any OPC UA compliant data source in a bidirectional manner.
Contents
Prerequisites
The UBIK® OPC UA components are acting as an OPC Client, therefore a secure connection to the respective OPC Server needs to be established in order to be able to communicate. The security standards that need to be applied are highly dependent on the server configuration and security infrastructure, but normally at least a client certificate needs to be issued that has to be trusted by the server:
- Open a command box on the UBIK® server with administrator privileges ("Run as administrator...")
- Run the program CreateCertifcate.exe from this archive
CreateCertificate.zip - CreateCertifcate.exe can be controlled via command line parameters, "CreateCertificate.exe -?"
- Open the program Manage computer certificates (typically C:\WINDOWS\System32\certlm.msc)
- Navigate to Personal - Certificates and find the certificate named UBIK OPCUA Interface
- Export the certificate and trust it on your OPC server
- It is essential that any Windows account trying to establish a secure connection using the client certificate (e.g., the IIS app pool user) must be able to read the private keys. This means that the certificate must be in a store location accessible by the account in question, and the account must have read rights for the certificate (this can be configured via MMC Snap-In "Certificates", using the "Manage Private Keys" task, but only for Personal Certificates). See also: https://stackoverflow.com/questions/2609859/how-to-give-asp-net-access-to-a-private-key-in-a-certificate-in-the-certificate/2647003#2647003
UBIK® Activities
| Activity | Category | Purpose (Short) |
|---|---|---|
| CreateOPCUAConnection | UBIK OPC UA Interface | Creates a new connection to an OPC UA data source |
| ConfigureOPCUAVariable | UBIK OPC UA Interface | Configures a single OPC variable in a connection for later access |
| CreateOPCUAScope | UBIK OPC UA Interface | Defines a scope in an OPC UA connection wherein variables can be accessed |
| AccessOPCUAVariable | UBIK OPC UA Interface | Reads or writes a single configured OPC UA variable |
Examples
Download example workflow 
OPCReadVariables.uwf for use against the OPC Quickstart Data Access Server.